Telephone-line selective-switch device.



J. H. SWANSON. TELEPHONE LINE SELECTIVE SWITCH DEVICE.

APPLICATION FILED MAILB, 1910. 1,035,493.

3 SHEETS-SHEET 1.

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COLUMBIA PLANOORAPM c0" WASHINGTON, D. c.

Patented Aug. 13, 1912.

' J. H. SWANSON.

TELEPHONE LINE SELECTIVE SWITCH DEVICE.

APPLICATION FILED MAR.8,1910.

1 35,493. Patented Aug. 13,1912.v

3 SHEETS-SHEET 2.

coLUMmA PLANOCIRAPH co., WASHINGTON. D. c.

J. H. SWANSON.

TELEPHONE LINE SELECTIVE SWITCH DBVIOE.

APPLICATION FILED HALE, 1910.

1,035,493. Patented Aug. 13,1912.

3 BKEETB-BHEBT 3. N W p B cin m J J r J l v 1 i f f i 9 if f i r//vd/vrm W Jomv m JW/7/V60/V COLUMBIA mNnallAPll to. WASHINGTON. h. c.

UNITED STATBSWIZATENT OFFICE.

JOHN HENRY: SWANSON, OF MINNEAPOLIS, MINNESOTA, ASSIGNOR OF ONE-HALF TOT. F. ROBINSON, 0F MINNEAPOLIS, MINNESOTA, AND ONE-HALF TO ROBINSONLOOMIS MOTOR TRUCK 00., OF MINNEAPOLIS, MINNESOTA, A CORPORATION OFMINNESOTA.

TELEPHONE-LINE SELECTIVE-SWITCH DEVICE.

To all whom it may cofloem:

Be it known that I, JOHN H. SwANsoN, of Minneapolis, Hennepin county,Minnesota, have invented certain new and useful Improvements inTelephone-Line Selective- Switch Devices, of which the following is aspecification.

The object of my invention is to simplify and improve the apparatusshown in Letters Patent of the United States, issued to me November 30,1909, No. 941,743.

My present invention has for its primary object the same generalfresultattained by the apparatus of my patent above referred to, butaccomplishes such result by a more reliable and greatly simplifiedmechanism at the substation, performing the operation with greatercertainty, eliminating chances of disorder and the possibility ofoperation of the substation apparatus by other than the applied currentof predetermined character.

My present invention aims to provide a substation apparatus operableonly by a steady current traversing the relay windings for the purposeof closing the main line conductors, and to effect the opening of thesubstation line apparatus by an alternating current traversing the saidwindings. The steady current applied for this purpose need not be inexcess as to quantity and measure of the alternating current.

In my present invention the electromagnet employed in the relaysubstation apparatus is equipped to offer the greatest possibleimpedance and self inductive resistance to analternating current. Iaccomplish this by providing an electromagnet solenoid having a primarywinding in the line circuit, and a local circuit winding that is shortcircuited from one core to the other of the magnet and is adapted tooffer an inductive resistance so that when an alternating current ispassed through the coils it will have no effect on the local circuitarmature but will repel the steel armature of the subscribers circuit. Ialso provide a local winding with each primary winding. I do not wish tobe confined to any special form of inductive winding, but I have foundthe coils, wound in a clockwise direction and a non-clockwise direction,are efficient for the Specification of Letters Patent.

Application filed March 8, 1910.

Patented A11 13, 1912.

Serial No. 548,040.

purpose designed. The electromagnet forming part of the substationapparatus has all the characteristic features of a slow acting magnet.To this end its iron cores are preferably long in proportion to theoutside diameter and as much iron is used as is practicable with a viewof offering impedance to the altering current magnetic flux.

In the accompanying drawings forming part of this specification, Figure1 is a. diagrammatic view of the central station connection and theapparatus at the substation connected therewitln'Fig. 2 is a side viewof a substation apparatus, Fig. 3 is a top view of the same, Fig. 4 isan end view, Fig. 5 is a diagrammatic view illustrating the connectionsof the subscribers circuit with the local circuit controlling device,the arrangement of the contact springs being slightly modified forconvenience of illustration.

In the drawing, a source of steady current is indicated at SC and asource of alternating current at M.

A represents a primary armature of soft iron, lying in a magnetic fieldof force parallel to the cores JJ, and flexibly supported upon branchpole pieces N-N and extending within the magnetic field of force towarda yoke C. The said armature is preferably Y-shaped and has its free enddirectly over the yoke C. The movement of the armature is limited by thescrew T. This screw passes through a hole in the armature and as thehole is slightly larger than the screw, the armature is free to movetoward and from the yoke C, the movement being limited by the head ofthe screw. The branches of the armature A are held down upon the polepieces N-N by means of screws SS and by this means I effect a moreperfect magnetic contact between armature A- and pole pieces N-N. Thescrews SS and springs R-R- are preferably of iron or steel to actpartially as conductors of magnetism between the pole pieces NN andarmature A. The armature A acts as a primary armature in a combinedlocal battery controller and the substation contact making apparatus forthe purpose of making contact between the main line conductors and thesubstation conductors. The armature A, lying between the ends of anelectromagnet, is Y-shaped and the fork of the Y is afiected by themagnetic influence in the said electromagnet when the free ends of theelectromagnetpresent a like polarity and the yoke of the electromagnetan opposite polarity. It will therefore be understood that if anarmature, such as I have herein referred to, can be placed with itsbranches upon the free ends of a U-shaped electromagnet and the fork ofsaid armature near the yoke of the said magnet, the fork will beattracted toward said yoke and when an exciting current traverses thecores to produce in the free ends of the U-shaped magnet magnetism oflike polarity, the yoke in said magnet will assume an opposite polarity.This exciting current is introduced into the main line by the operatorat the central station by means usually employed for this purpose, theconnection with the source of energy being arranged so that currents oflike sign will be introduced on both sides of the line simultaneously.As shown, this exciting current is controlled by the key K whichconnects both lines ML with one side of the battery or the battery SC,or the source of direct current. The other side of the battery isconnected to a ground, and the windings I, I, are also connected at I toa ground, thereby forming a circuit whereby a direct current may bepassed from a battery or other source through the windings about thepole pieces of the'magnet in multiple. The yoke or central point in theU-shaped magnet will be energized and the two pole pieces at theopposite end of the magnet will also be energized, the pole pieceshaving magnetism of like signs opposite from the yoke at the neutralpoint. The Y-shaped magnet will thereupon be attracted to close thelocal circuit. Upon breaking the circuit through the main line thesprings connected with the soft iron armature will return it to itsnormal position, breaking the local circuit. The closing of the localcircuit energizes the pole pieces through said local circuit windings toattract the steel armature and close the subscribers circuit, "Thiswill. remain closed until an alternating current is passed through themainline when the steel arma ture will be repelled'and the subscriberscircuit broken.

I will now proceed to describe in detail the apparatus by which I preferto accom-' plish the making and breaking of the circuits through thesubstation relay.

A flat spring D is secured to armature A, projecting over yoke C andcontact screw U, serving as a contact spring in the local batterycircuit. Q is a non-magnetic bar extending across the branches ofarmature A and acting as a fulcrum for the spring D. Screw L, supportedby stud X, secured to the front plate Z by screw W permits theadjustment for the spring D and tension of armature A. The electromagnetyoke C, secured to magnetic cores JJ by screws VVW, has in its middleportion an extension bent at an angle forward and toward the pole piecesN-N to conduct the magnetic flux in its natural course. Secured to andinsulated from the yoke C by insulated washer Y is a stud M, throughwhich contact screw U extends to form in part the local battery circuit.The front plate Z is of non-magnetic metal and may be made in variousforms and I do not wish to be confined to the particular type'hereinshown.

The steel armature B herein shown is supported and pivoted across theelectromagnet cores JJ and is free to move to ward and from said cores.A tensionspring E holds the steel armature away from the magnetic coreswhen not attracted.

By referring to Fig. 1, the substation ap- I paratus is represented withthe windings upon the electro-magnet cores. L-I, representing. theprimary windings of the relay, are wound upon the electromagnet coresJJ. M L represents themain line conductors extending from the centralstat-ion to the substation, and to which the terminals of the primarywindings II are connected in multiple when the battery current impressedupon both the central station lines in multiple, and which windings I,I, are connected in series when an alternating current or a directcurrent is impressed upon the central station lines in series. Theapparatus at the central station includes a switch board jack J, avisual signal I), a plug P, and switch board cords or conductors S. S-Cis the source of steady current, above referred to, controlled bycurrent closing key K. The source of alternating current M is controlledby key K. By the insertion of plug P into'jack J and depressing thekeyK, a steady current is directed into line ML which completes itscircuit through primary windings I -I; By these means the electromagnetcores JJ become magnetically charged, the pole pieces N N assume apolarity of like sign, and the yoke C assumes apolarity of oppositesign. The effect is to attract armature A and close local circuitthrough battery A, contact spring D and screw U, conductors B and localbattery windings K-K. These are oppositely wound upon the cores JJ so asto induce in the free ends of the cores a polarity of opposite sign. Thesteel armature B is thereby attracted to the core ends JJ. Theapplication of the steady cur rent at the central station may now bebroken, whereupon the armature A is re v lieved of attraction in theyoke C and is drawn away from the contact screw U by fiat spring D,thereby openingthe' local b attery circuit. The steel armature remainsin its attracted position, and the circuit remains closed through thesubscribers line. WVhen it is desired to release the steel armature fromthe ends JJ and thereby open circuit in spring contact P, an alternatingcurrent is applied to line conductors M-L. This current, traversing theprimary windings, II, will induce in the magnetic cores JJ a feeblemagnetic flux of an alternating character, causing the steel armature Bto be repelled from the cores J J, thereby opening the spring contactscontrolled thereby.

I prefer to provide a winding H on each magnet, inclosing the primarywinding, the ends of the winding H, which I may prefer to designate asthe local winding, being joined together to form independent coils foreach core. These windings, as shown clearly in Fig. 1, are purely localand their presence has the effect of increasing the impedance in theprimary winding to an alter nating current. Said windings will have nofunction however, when a direct current is used.

Referring to the diagrammatic view Fig. 5, the contact springs I and Pare in circuit with the main line conductors and carried by the steelarmature B and adapted to close the circuit through the subscribers line4 and 5. These contact springs P and P, as indicated in Fig. 2, engageinsulated stop screws X, which limit the movement of the springs in onedirection.

From the foregoing it will be understood that the alternating current,traversing the windings II, does not in any way influence the armatureA, consequently the application of the alternating current to the mainline conductor will not close the local battery circuit, but will causethe release of the armature 13. Furthermore, the local battery current,taver-sing the windings K--K, will not in any way affect armature A. Thesoft iron armature lies parallel to the electromagnet cores, its freeend is directly in a neutral field when the free ends of the said coresare influenced by the alternating current to release the steel armature;that is, when said free ends are magnetically charged so that theypresent unlike polarity. By well known physical laws, the centralportion of such a U-shaped magnet will be neutral or dual as tomagnetism, thus leaving the soft iron unaffected. Hence the alternatingcurrent in main line colt ductors ML ML will not affect the soft ironarmature. To affect the soft iron armature A, it is necessary to causecurrent of like signs to be applied to the two sides of the lineconductors M-L M'IJ simultaneously by connecting the two sides with onepole of the battery in multiple and ground their opposite end throughwindings I-I and the other pole of the battery to ground. The effect ofthis is to excite in the electromagnet cores JJ magnetism of like signsin their free ends and magnetism of the opposite polarity, therebyattracting soft iron armature A.

I am thus able, by the application of a direct, steady current, to closethe local circuit through the soft iron armature, the closing of thelocal circuit energizing the core ends to attract the steel armature andclose the substation circuit. This circuit, through the substation line,will remain closed as long as required, the direct current being cut offin the meantime from the main line. As soon as it is desired to open thesubscribers circuit the operator will apply the alternating current tothe main line whereupon the steel armature will be repolled from themagnet cores and the subscribers circuit opened, all without afl'ectingthe armature A or again closing the local circuit.

This relay may be utilized in a telegraph as well as a telephone circuitand for signaling purposes generally, and I do not wish to be confinedentirely to the use herein described and set forth. The local coil forthe magnets forms an important feature of the invention, as it insuresthe release of the steel armature without in any way affecting thearmature of the local circuit.

I claim as my invention:

1. The combination with a central station line, and a substation linenormally disco-nnected from said central station line, and having asubscriber station, of means for automatically connecting anddisconnecting said substation line to and from said central station lineincluding a relay comprising parallel cores, means for passing a currentin multiple about said cores, a soft iron armature energized by saidcurrent, a local circuit for said relay controlled by said armature, asteel armature energized by said local circuit, devices controlled bysaid steel armature for making and breaking the connection between thesubstation line and the central station line, and means for passing acurrent about said core in series for repelling said steel armature,said soft iron armature being so disposed as to be unaffected by thecurrents passing in series about said cores.

2. The combination with a central station line, and a substation linenormally disconnected from said central station line, and having asubscriber station, of means for automatically connecting anddisconnecting said substation line to and from said central stationline, including a relay comprising parallel cores, means for passing adirect current in multiple about said cores, a soft iron armatureenergized by said current, means for passing a local current about sa'idcores in series, devices for controlling said local current operated bysaid soft iron armature, a steel armature, devices controlled by saidsteel armature for making and breaking the connection between thesubstation line and the central station line, said steel armature beingso disposed relative to the cores, as to be moved by the local circuitpassing about the cores, and means for passing an alternating currentabout the cores in series, for repelling said steel armatures to breakthe connect-ion with the central station line, said soft iron armaturebe ing so disposed as to be unaffected by the current passing in seriesabout said cores.

3. The combination with a central station line, and a substation linenormally disconnected from said central station line, and having asubscriber station, of means for automatically connecting anddisconnecting said substation line to and from said central stationline, including a relay comprising parallel cores having a connectingyoke at one side thereof, a soft iron armature hav ing its movable partadjacent said yoke, a steel armature adjacent the free ends of saidcores, primary windings on said cores,means for passing a direct currentin multiple through said primary windings, whereby said soft ironarmature is energized, a local battery, windings arranged in series onsaid cores, devices for connecting said windings to the local battery,controlled by said soft iron armature, the current of said local batteryenergizing said cores for attracting said steel armature, and means forpassing acurrent through said primary winding in series for repellingsaid steel armature, and devices controlled by said steel armature formaking and breaking the connections between the substation line, and thecentral station line.

a. The combination with a central station line and a substation linenormally disconnected from said central station line, and having asubscriber station, and means for automatically connecting anddisconnecting said substation line to and from said central stationline, including a relay comprising parallel cores, a yoke connectingsaid cores at one end of said relay, a soft iron armature lying in aplane substantially parallel to the longitudinal axes of the cores, andhaving a movable end adjacent the central part of said yoke, a steelarmature located adjacent the free ends of said cores, a primary windingon said cores adjacent the yoke, means for passing a direct currentthrough said primary windings in parallel, whereby the soft ironarmature is energized, windings on said cores adjacent the free endsthereof, a local battery, devices for connecting said local battery withsaid windings adjacent the free ends of the cores, said devices beingcontrolled by the movable soft iron armature,

devices for connecting the substation line to the central station linecontrolled by said steel armature, and means for passing an alternatingcurrent in series through the primary windings for repelling the steelarmature to disconnect the substation.

5. The combination with a central station line and a substation linenormally disconnected from said central station line, and having asubscriber station, of means for automatically connecting anddisconnecting said substation line to and from said central stationline, including a relay comprising parallel cores, means for passing adirect current in multiple ab gut said cores, a soft iron armatureenergized by said current, means for passing a local current about saidcores in series, a local circuit for said relay, devices operated bysaid soft iron armature for controlling said local circuit, a steelarmature, devices controlled by said steel armature, for making andbreaking the sub station line and the central station line, said steelarmature being so disposed relative to the cores as to be moved by thecurrent in the local circuit passing about the cores, means for passingan alternating current about the cores in series for repelling'saidsteel arn'iature, said soft iron armature being so disposed as to beunaffected by the current passing in series about said cores, and closedsecondary windings located upon each of the cores.

G. The combination with a central station line, and a substation linenormally disconnected from said central station line, and having asubscriber station, means for automatically connecting and disconnectingsaid substation line to and from said central station line, including arelay comprising par allel cores, a yoke connecting said cores at oneend of said relay, a soft iron armature lying in a plane substantiallyparallel to the longitudinal axes of the cores, and having a movable endadjacent the central part of said yoke, a steel armature locatedadjacent the free ends of said cores, a primary winding on said coresadjacent the yoke, means for passing a direct current through saidprimary windings in the parallel whereby the soft iron armature isenergized, windings on said cores adjacent the free ends thereof, alocal battery, devices for connecting said local battery with saidwindings adjacent the free ends of the cores, said devices beingcontrolled by the movable soft iron armature, devices for connecting thesubstation line to the central station line controlled by said steelarmature, and means for passing an alternating current in series throughthe primary windings for repelling the steel armature to disconnect thesubstation, and closed secondary windings located upon each of thecores.

7. The combination with a central station line, and a substation linenormally disconnected from said central station line, and having asubscriber station, and means for automatically connecting anddisconnecting said substation line to and from said central station lineincluding a relay comprising parallel cores, a yoke connecting saidcor-es, at one end of the relay, a Y-shaped soft iron armature locatedin a plane substantially parallel with the axes of the cores, the outerends of the armature being rigidly supported and the connected movableend of the armature being disposed adjacent the central part of saidyoke, primary windings on said cores, means for passing a direct currentthrough said cent 'al station line and the primary windings in multiplewhereby the soft iron armature is attracted, windings on said cores, alocal battery, devices for connecting said local battery to said lastnamed windings, said devices be ing controlled by the movable armature,a hardened steel armature adjacent the free ends of said cores, saidsteel armature being energized and attracted by the local currentpassing in series through the windings on the cores, devices forconnecting the substation line to the cent 'al station line, controlledby said hardened steel arn'iature, and means for passing an alternatingcurrent in series through the primary windings for repelling thehardened steel armati'lre to disconnect the substations.

8. The combination with a'eentral station line and a substation linenormally disconnected from said central station line and having asubscriber station, and means for automatically connecting anddisconnecting said substation line to and from said central stat-ionline, including a relay comprising parallel cores, a yoke connectingsaid cores at one end of the relay, a Y'shaped soft iron armaturelocated in a plane substantially parallel with the axes of the cores,the outer ends of the armature being rigidly supported and the connectedmovable end of the armature being disposed adjacent the central part ofsaid yoke, primary windings on said cores, means for passing a directcurrent through said central station line, and the primary windings inmultiple, whereby the soft iron armature is attracted, windings on saidcores, a local battery, devices for connecting said local battery tosaid last named windings, said devices being controlled by the movablearmature, a hardened steel armature adjacent the free ends of said coressaid stationary armature being energized and attracted by the localcurrent passing in series through the windings on the cores, devices forconnecting the substation line to the central station line con-- trolledby said hardened steel armature, means for passing an alternatingcurrent in series through the primary windings for repelling thehardened steel armature to disconnect the substation, and closedsecondary windings on each of the cores offering an impedance to saidalternating current.

ing its movable part located adjacent the end of the cores at one end ofthe relay, primary windings on said cores, means for passing a currentin multiple through said windings for attracting said armature, a localbattery, windings on said cores, whereby a current from the localbattery may be passed in series about said cores, devices forcont-rolling said local circuit operated by said armature, a hardenedsteel armature at the other end of the relay adjacent the ends of thecores, whereby said local current passing in series about said coreswill attract said steel armature, devices forconnecting the main line tothe substation line controlled by said steel armature, and means forpassing an alternating current through said primary windings in seriesfor repel-- ling the steel arn'lature.

10. The combination of a main line and a substation line, of means forconnecting and disconnecting said lines including a relay, comprisingcores, a soft iron armature having its movable part located adjacent theend of the cores at one end of the relay, primary windings on saidcores, means for passing a current in multiple to said windings forattracting said armature, a local battery, windings on said cores,whereby a current from the local battery may be passed in series aboutsaid cores, devices for controlling said local circuit operated bysaidarmature, a hardened steel armature at the other end of the relayadjacent the ends of the cores whereby said local current passing inseries about said cores will attract said steel armature, devices forconnecting the main line to the sub line controlled by said steelarmature, means for passing an alternating current through said primarywindings in series for repelling the steel armature, and secondaryclosed windings on said. cores, offering impedance to the alternatingcurrent.

11. The combination, with a central station line, of a relay consistingof a U-shaped magnet, an arn'lature, a local circuit con trolled by saidarmature, the application of currents of like sign to said centralstation lines producing magnetism of same polarity at the oppositecorresponding poles of said U-shaped magnet and magnetism of oppositepolarity at the other or neutral point of said magnet, saidmagnet havingwindings thereon in circuit with said local circuit, a steel armatureattracted by the cores of said last named windings and a subscriberscircuit and station controlled by said steel armature.

12. A relay comprising a magnet having,

pole pieces at one end and an opposite neutral point, a primary windingfor said magnet and a line circuit therefor, an armature, a localcircuit arranged to be closed by the attraction of said armature to saidneutral point, said local circuit being broken when the circuit isopened in said main line, su-bscribers circuit, and means for closingthe same by the closing of said local circuit, said subscribers circuitremaining closed after the opening of said local circuit, and meanswhereby the passage of an alternating current through said primarywinding will disconnect said su-bscribers circuit, said armature beingso disposed as to be unaffected by said alternating current.

13. A relay comprising an electro-magnet having a primary winding and amain line circuit connected therewith, a local circuit, an armatureattracted by the passage of a direct current through said main line andprimary winding to close said local circuit, a subscribers circuit, anarmature therefor energized by the closing of said' local circuit toclose said subscribers circuit, and an independent inductive winding forsaid magnet adapted to render an alternating current in said primarywinding ineffective to-close said local circuit, but causing it to repelsaid subscribers circuit armature and. open said subscribers' circuit.

, 14. A relay comprising a magnet U- shaped in form and provided with aprimary winding a mainline circuit adapted to be connected with saidprimary winding,

a local circuit and means for closing said local circuit when a directcurrent is passed circuit but effective to repel said steel armature andopen said subscribers circuit.

15. The combination with a first line, and a second line normallydisconnected from said first line, of means for automatically connectingand disoonnectlng said second lme' to and from sald first line,-1nclud1ng a relay,-

means for passing a current in multiple through the windlngs of saidrelay, a soft iron armature adapted to be attracted by the passage ofsaid current, a local circuit for said relay controlled by saidarmature, a steel armature attracted by the closing of said localcircuit, devices controlled by said steel armature for making andbreaklng the connection between the first line and the second line, andmeans for passing the current through the relay windings in series,

for repelling said steel armature, said soft iron armature being sodisposed as to be" unaffected by the currents passing in serles athroughsaid windings.

In witness whereof I have hereunto set my hand this 24 day of Februarv1910.

JOHN HENRY SVVANSON. .Vitnesses:

L. C. CRoNEN, J. A. BYRNES.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents, Washington. D. G.

